In many scientific fields inclusive of biology, chemistry, physics, medicine and pharmacology, small amounts of various fluids of high monetary and research value are maintained in containers having necked openings such as vials which here before have been sealed with threaded cap devices and other means of a more permanent nature. These high value fluid materials require safe and more readily available access than afforded by for example a srew on cap. In addition, frequently several vials of related vials of reagents necessary for specific laboratory testing and the like are maintained in close proximity, for example, in predetermined clusters or racks. In the field of diagnostic testing of biological fluids for the presence of drugs, viral disease, bacterial infections and the like, samples are collected, reacted with reagents, and the results of the reactions analyzed using well known techniques. The reagents used in such tests are typically purchased in and drawn from vials or other containers which are often arranged for convenience in pre-formed packs having a plurality of such vials containing the reagents required for a specific test. Typically, samples of body fluids such as serum, plasma, urine and the like are assayed for the presence of analytes such as drugs, viruses or bacteria by reacting the samples according to a specific test protocol with specific reagents which are selected to identify a particular analyte. The protocol specifies the sequence in which sample and reagent are to be introduced, the timing of the introduction of sample and reagents, the volumes of each to be used and other conditions to be controlled such as temperature. The resulting reaction mix is typically allowed to incubate for a predetermined time and then read, optically or otherwise to determine the presence of concentrations of the specific analyte which the assay is designed to identify. In general, procedures and apparatus for preparing and reading immunoassays are well known.
For economy and practicality, each vial typically contains sufficient amounts of reagent to test a number of samples. Multiple dose reagent pack and carousels for automated clinical analyzer systems are known wherein the reagent pack is adapted to function within the carousel, the carousel holding such packs together with a plurality of conventional sample containers which contain samples to be assayed by the analyzer. These reagent packs include a vial carrier having a plurality of vial receiving wells for containing a corresponding plurality of muli-dose reagent-containing vials. The carousel includes a base for rotably mounting in an analyzer and a rack which is connected to the base and which has a plurality of predetermined mounting positions which are adapted to releasably mount the reagent packs or reagent vials in selected positions.
Automated clinical analyzers are capable of performing immunoassays on an entire batch of samples simultaneously. In some types of known analyzers, such as the well known TDx.RTM. clinical analyzer manufactured by Abbott Laboratories of North Chicago, Ill., a batch of sample containers are mounted radially about a ratable carousel together with a corresponding number of reaction containers. The carousel is then mounted inside the analyzer. Inside the analyzer, the carousel rotates step wise to move each corresponding sample container and reaction container pair first to a position adjacent a preparation station, and then to a second position adjacent a reading station. A mechanical apparatus having pipetting means and typically operating under program control is located in proximity to the preparation station. Also located in proximity to the preparation station are a plurality of reagent containers which contain the reagents required to perform a specific immunoassay on the batch of samples contained in the sample containers. The reagent containers may be individual containers or may be configurated as an integrated pack.
At the preparation station, the mechanical apparatus and pipetting means operate to access and transfer volumes of sample from a sample container and reagents from the reagent containers into a reaction container according to the protocol established for the specific assay. When the mechanical apparatus completes the preparation of the reaction mix according to the test protocol the carousel rotates, positioning the next corresponding sample container and reaction container pair adjacent to preparation station and moving the previous pair toward the reading station. Known carousels typically hold between 20 and 25 sample containers.
One limitation of a number of these analyzers is that they are capable of performing only one assay at a time on each batch of samples on the carousel. In order to perform a different assay, it is necessary to physically remove the reagent containers either individually or as a pack from the analyzer and replace them with different reagent containers or a different pack for the assay to be run. The requirement of changing reagent packs for each assay has an adverse impact on throughput of the analyzer. However, more recently multi-dose reagent packs have been provided which can be expediently mounted on a carousel with a plurality of sample containers to provide reagents for conducting immunoassays of a plurality of such samples. The carousels are adapted to hold a plurality of such multi-dose reagent packs interspersed with such sample containers to flexibly provide reagents for performing the same or different assays on the same or different samples. Flexibility has been achieved in providing apparatus and methodology wherein a selected plurality of different assays on the same or different samples may be achieved as well as selectably vary the number of different assays performed on each sample while maintaining high throughput levels and reducing the requirement for physical interaction with the analyzer and the carousel.
A problem with such multi-dose reaction packs, multi-sample carousel analyzer apparatus is that once opened, the reagents may become contaminated. For example, the properties of certain reagents may be affected by exposure to light or air, the passage of time, or exposure to other reagents or contaminates.
The vials of such packs could be individually reclosed using individual screw on or other closures typically provided with such vials. However, such individual closures can be misplaced or lost when separated from the respective vials. In addition, it is time consuming and in convenient to individually open and reclose each vial of a pack with a separate closure, particularly in an automatic testing environment where test set up time and the time between tests can have a critical impact on throughput.
A need exists for a snap cap apparatus that provides expedient, economical, secure and safe resealing of individual or multiple dose reagent vials once the vials have been opened. A desirable feature of such apparatus is to provide resealing of a group of vials arranged in a reagent pack. Another needed feature is to provide an apparatus which minimized contamination during handling and loss of seal during the useful life of the reagents. It is advantageous to provide a sealing apparatus that remains attached to the vials of the reagent pack during use of other reagent packs in an automated clinical analyzer without interfering with other assay protocol operations.